In utility vehicles such as tractors, it is conventional to provide a liquid crystal display part in an instrument panel that has a tachometer for indicating the rotational speed of an engine and various indicator lamps and show various information in the liquid crystal display part.
For example, Patent Document 1 below discloses a work vehicle including an engine, a speed control lever operated to change the output rotational speed of the engine, a main transmission and an auxiliary transmission that change the speed of rotary power from the engine, a main shift lever and an auxiliary shift lever respectively operated to change the speed-changing status of the main transmission and the auxiliary transmission, an instrument panel including the liquid crystal display part, and a control device, wherein an actual vehicle speed based on a speed sensor, the current speed-changing status (the activated speed-changing stage) of the main transmission expressed using the vehicle speed attained when the engine is at a rated rotational speed (a rated vehicle speed) at the current operational position of the main shift lever, the current speed-changing status (the activated speed-changing state) of the auxiliary transmission, and a set vehicle speed based on the current rotational speed (a set rotational speed) of the engine obtained from the operational position of the speed control lever are shown in parallel on the liquid crystal display part.
With the configuration described in Patent Document 1, an operator can recognize the actual vehicle speed, the activated speed-changing stage of the main transmission, the activated speed-changing stage of the auxiliary transmission, and the set vehicle speed merely by looking at the liquid crystal display part of the instrument panel without directly looking at the operational states (the operational positions) of the speed control lever, the main shift lever, and the auxiliary shift lever.
However, in the configuration described in Patent Document 1, what is shown in the liquid crystal display part is information relating only to the vehicle speed at that time.
That is, the configuration described in Patent Document 1 is for showing the vehicle speed at that time obtained based on the activated speed-changing stage of the main transmission at that time, the activated speed-changing stage of the auxiliary transmission at that time, and the output rotational speed of the engine at that time, and is not for informing an operator in advance of how the set vehicle speed and the actual vehicle speed change in accordance with operations on the speed control lever, the main shift lever, and/or the auxiliary shift lever.
Work vehicles such as tractors are provided with a working-system power transmission path that transmits rotary power from an engine to a PTO shaft via a PTO transmission in addition to a traveling-system power transmission path that transmits rotary power from the engine to travel members such as driving wheels via a main transmission and an auxiliary transmission.
The rotary power that is output from the PTO shaft serves as power to drive a working device such as a rotary tiller, and an operator changes speed-changing stage of the PTO transmission via a PTO shift lever in accordance with the activating state of the working device to cause an output rotational speed suitable for the activating state at that time to be output from the PTO shaft.
However, there is no conventional work vehicle that is configured to inform in advance an operator of how the output rotational speed of the PTO shaft changes when the PTO transmission is activated or operated to change the output rotational speed thereof.
That is, with conventional work vehicles, when an operator, judging from the activating or operating state of the working device, wishes to increase the output rotational speed of the PTO shaft, the operator has to determine from his own knowledge and experience how far the output rotational speed of the PTO shaft increases when the PTO transmission is shifted to a higher speed-changing stage.
Accordingly, in some cases, the operator needs to repeat actually shifting the PTO transmission toward a higher speed side, for example, for only one speed-changing stage, then checking the activating state of the working device, and judging whether it is still necessary to shift the PTO transmission.